@Huzi
The guy who tried importing cork bark tubes is me. In the thread about the importing of cork bark tubes you will see that in the end it was going to be extremely expensive to import the virgin cork bark tubes. The price from the supplier in Portugal "if I remember correct" was extremely over priced, and on top of that I had to calculate in the container hire, shipping cost, import tax and normal tax once sold. Hallo SARS which would end up with me and a full container of cork bark tubes

.
So the next viable solution for all is to use flat cork bark slabs found at Animal Kingdom sold at R120 per Kg. Take the piece you would want to make your tube, fill a bucket/tray or bath

with the hottest water and keep the cork submerged in the water. I leave mine over night. Now look for an object you would like to wrap the cork bark around to form a tube. I used a spray paint can, and with the aid of tiebacks, and rope I wrapped the piece of cork bark around the can so that the sides touch. You don't want it to overlap. Set it out to cool down or dry out. While it is on the can apply your hot glue and you have your tubes.